First problem, .25 ACP balls are usually .250 in diameter or approx. .257 Rob calls for bullets that are .257/.258 in diameter. Ergo, you have to do something to enlarge the bullet or it wobbles and accuracy ISN'T. As said, you can paper patch anything, but getting two wraps in .007... and something this small... makes my fingers sore thinking about it. There are "onion skin" / "copy" papers that might work. And if it is a bit large, you can run it thru a size die (and lubricate it too if you like). 1500 no problem here.
If you are willing to use lead bullets, you can upset them by tapping with a mallet. If you want precision, you support them in a die of some sort. This would get you a groove filling bullet. Well lubed and you can go to the Lyman manual for loads. Might not have bullets quite this light, but fast powders, no big deal. IMR had a manual out that listed loads for all their powders in each round. The 4831 loads for .22 hornet or .222 were silly, but informative.
It has been done. The other option are the chamber inserts that allow you to shoot the whole cartriddge in the larger chamber. luck.